ifft2 (Signal Processing Toolbox)

Two-dimensional inverse fast Fourier transform.

Syntax

Y = ifft2(X)
Y = ifft2(X,m,n)

Description

Y = ifft2(X) returns the two-dimensional inverse fast Fourier transform (FFT) of the array X. If X is a vector, Y has the same orientation as X.

Y = ifft2(X,m,n) truncates or zero pads X, if necessary, to create an m-by-n array before performing the inverse FFT. The result Y is also m-by-n.

For any X, ifft2(fft2(X)) equals X to within roundoff error. If X is real, ifft2(fft2(X)) may have small imaginary parts.

The ifft2 function is part of the standard MATLAB language.

Algorithm

The algorithm for ifft2 is the same as that for fft2, except for a sign change and scale factors of [m n] = size(X). The execution time is fastest when m and n are powers of two and slowest when they are large primes.

See Also

fft
One-dimensional fast Fourier transform.

fft2
Two-dimensional fast Fourier transform.

fftn
N-dimensional fast Fourier transform (see the MATLAB documentation).

fftshift
Rearrange the outputs of fft and fft2.

ifft
One-dimensional inverse fast Fourier transform.

ifftn
N-dimensional inverse fast Fourier transform (see the MATLAB documentation).

`fft`	One-dimensional fast Fourier transform.
`fft2`	Two-dimensional fast Fourier transform.
`fftn`	N-dimensional fast Fourier transform (see the MATLAB documentation).
`fftshift`	Rearrange the outputs of `fft` and `fft2`.
`ifft`	One-dimensional inverse fast Fourier transform.
`ifftn`	N-dimensional inverse fast Fourier transform (see the MATLAB documentation).

ifft impinvar